Observation 47616: Xylaria Hill ex Schrank
When: 2010-06-25
Who: zaca
No herbarium specimen

Proposed Names

30% (4)
Recognized by sight
52% (2)
Recognized by sight
85% (1)
Recognized by sight
60% (2)
Used references: Fournier, J., Flessa, F., Peršoh, D., & Stadler, M. (2011). Three new Xylaria species from southwestern Europe. Mycological Progress, 10(1), 33-52.
Based on microscopic features: spores!
25% (1)
Used references: Læssøe, T. (1992). Xylaria digitata and its allies–delimitation and typification—I. Persoonia-Molecular Phylogeny and Evolution of Fungi, 14(4), 603-613.
Based on microscopic features: Spores!

Please login to propose your own names and vote on existing names.

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Thanks again, Roo!
By: zaca
2016-08-31 16:26:32 CEST (+0200)

I will be more attentive to Xylaria specimens in the forthcoming season.

By: Roo Vandegrift (Werdnus)
2016-08-30 20:44:50 CEST (+0200)

Thank you for your kind words, Zaca. I did ask Marc Stadler about it, and he said: “I guess you are right [about X. cinerea]. But I do hesitate to give a safe ID based on the Images. There are surely other species out there. And as I told you, Jacques knows Xylaria much better… He will probably tell you that you should send the specimen.”

I know you didn’t save this one, but in general Xylaria are pretty mysterious still, and ridiculously easy to preserve: just air dry them for a few days. They also often grow on the same log for a few years, if you ever find yourself back in the vicinity! You can send collections to folks like me or Jacques for work, or deposit them in a public herbarium (which is, in many ways, the better option, because it makes them broadly accessible).

Not posted on AscoFrance or elsewhere.
By: zaca
2016-08-30 12:16:03 CEST (+0200)

Thank you very much for your comments with a very rich content. Unfortunately, this observation is a bit to old for recalling the details and I didn’t preserved the specimen. It came for my starting of mushroom (in broad sense) observations. At that time I was not aware of the diversity in this genus (and others, btw) and, as Roo said, the field guides only refer very few species. Roo is also right about the willing of people to give the names for species, even in most cases they don’t have means to decide; as he said, it is a cultural affair (of this and of many others websites).
I hope Roo will keep giving his expertise in this type of fungi, enriching all of us with his opinions.

By: Roo Vandegrift (Werdnus)
2016-08-30 01:39:16 CEST (+0200)

Has anyone posted this on AscoFrance? I know Marc and Felipe both respond to queries there.

And, as to Danny’s (myxomop) original point about applying names super broadly: that’s as much to do with the culture as the forum. That Xylaria polymorpha gets thrown around on MO all the time reflects that people really want a specific name, and it reflects that most guide books list all of two Xylaria: X. hypoxylon and X. polymorpha. Of course people put that name on things — what else can they do!? What’s needed is a cultural shift to being okay with genus, or even higher order, identifications, and an understanding that (particularly for ascomycetes) the guidebooks are far from all inclusive.

And I think those are lessons that people are ready and willing to learn, if we are willing to teach respectfully. Take this observation as an example: Zaca was perfectly willing to accept a genus-level determination after understanding what was going on (and willing to dig into the diversity question deeper), but until someone explained, how was ze suppose to know what was wrong with X. polymorpha? It’s what the guidebook said, afterall!

The other thing that we need, of course, is a relatively comprehensive guide to the Xylaria of the world: there are more than 800 described species in the genus, and no place with more than a few dozen in any single key.

Hey! I’m an expert (I guess)!
By: Roo Vandegrift (Werdnus)
2016-08-30 01:25:16 CEST (+0200)

Hi Zaca,

It still feels a bit odd to say that, but I guess it’s true. There’s precious few of us working on Xylaria right now, and I’m one of them. This is a really interesting (and beautifully illustrated) observation; we’d be lucky if everyone posted such complete information!

To the identification: continental European Xylaria are a bit out of my experience, but I know my way around the literature, so I did some poking. The closest match I can find is a relatively recently described species called Xylaria cinerea, from Jaques Founier and Marc Stadler. That species is described as having ascospores 13–17 × 5–6 µm, (mean=14.8 × 5.5 µm, n=30), which is a little small for your specimen. The other option is Xylaria digitata, which is a Linnaeus species re-typified by Laessøe in the early ‘90s. That taxon is suppose to have spores 15.8–21.8 × 4.6–6.9 (mean=17-19.5 × 5.2–6). Better in the length range, but the ratio is a bit more off there; but, I think there’s a good chance that your width measurements are inflated, given the way that the spores are cracked and splayed open in the micrograph you posted. This happens all the time.

Of the two, I’m leaning towards X. cinerea, because of the ratio of length to width, because of the germ slit ( 2/3–4/5 spore-length in X. cinerea, vs. 1/4–1/3 in X. digitata), and because of the macromorphological differences (X. digitata can occur singly, but is usually branched; X. cinerea has ostioles that are “faintly to coarsely papillate, bluntly conical, black”, which fits your first picture nicely).

I’d like to ask Marc Stadler about this, and then get back to you. In the meantime, here’s the papers describing those species:

Fournier, J., Flessa, F., Peršoh, D., & Stadler, M. (2011). Three new Xylaria species from southwestern Europe. Mycological Progress, 10(1), 33-52.

Læssøe, T. (1992). Xylaria digitata and its allies–delimitation and typification—I. Persoonia-Molecular Phylogeny and Evolution of Fungi, 14(4), 603-613.


By: zaca
2010-08-17 01:41:41 CEST (+0200)

Thanks, myxomop, for you kind words.
I still hope that some expert on the subject can give light to the species of this specimen. In the meantime, I learned to make the preparations of these kind of fungi to observe under the microscope, and I have used that knowledge to other observations in MO, so the time I devoted to it was well spent.

By: Danny Newman (myxomop)
2010-08-17 01:22:05 CEST (+0200)


You’ve certainly done a commendable amount of grunt work on this observation. I wish I were the expert I spoke of in an earlier comment so I might provide some insights/possible matches, but I know only enough of the pyrenomycetes to have cast my initial doubt and illustrate the reasons why. My usefulness ends here. At the very least, the foundation is laid for when some glutton for Xylaria punishment decides to take on the challenge.

Thank you for your thoroughness and persistence. This has become a most interesting and exemplary observation to follow.

By: zaca
2010-07-06 20:14:10 CEST (+0200)

I have already uploaded two sets of pictures with the results of the microscopy. Considering only the spores measures and using the results for the most known species of Xylaria available at “mushroomexpert” and “mykoweb”, the latter for the case of X. hyphoxylon (results in microns):
X. polymorpha : 20 – 31 × 5 – 10
X. hyphoxylon: 10 – 14 × 4 – 6
X. longipes: 13 – 15 × 5 – 7
X. longiana: 9 – 11 × 4 – 5
I think that the first conclusion to draw is that the specimen analised does not belong to any of these species. In fact, the spores are sufficient wide but not long enough to belong to X. polymorpha, and, on the other hand, they are too wide and too long to belong to anyother of the above mentioned species.

I feel that myxomop is right
By: zaca
2010-07-02 23:37:40 CEST (+0200)

about the use of term conversation rather than controversy, since usually the latter has a negative charge that is not appropriate this forum. After his reaction to this observation I agree that perhaps I might have precipitated in giving the epithet “polymorpha” to this specimen, but it seemed natural to me in the face of the forms of Xylaria I have found before. This means that with the available data, the safest is to use Xylaria sp., as myxomop now proposes. I have no personal microscope, but I have access to one sporadically. I’ll make a preparation to observe in a forthcoming oportunity and I’ll put the data here.

By: Danny Newman (myxomop)
2010-07-02 04:42:15 CEST (+0200)

zaca: Just conversation, not controversy. I think Xylaria is a safe bet. I agree that the description is all over the place, giving a very broad spectrum of morphological characteristics as diagnostic for X. polymorpha, though from the sound of the epithet it would appear that “many forms” are to be expected. As always, photomicroscopy could always lend a hand if you have the means to do so at your disposal.

Paul: do you have a link for the facebook page?

It was not my purpose to enter into controversy about this observation …
By: zaca
2010-06-28 15:10:46 CEST (+0200)

But, since I did not bring this issue to debate, I give my opinion. I think people tend to call the same name to different things because the existing descriptions permit, as they are vague. Denny Newman gives us here an example of a description of X. polymorpha which is anything but precise. In fact, in that description, which is the true meaning of the following sentences:
- … mostly obtuse; or obovote, compressed, more or less divided sublobate, globose or otherwise irregular in shape…
- … dirty-brown at first, becoming black, …
- … very variable in size from 2-4 cm. high and 1/2 cm. thick to 8-11 cm. high and 2-3 cm. thick. …
- … Perithecia crowded, tolerably large, ovate or globose, with the papilliform ostiolum …
and, by the way, which ones do not apply to my specimen (relative to the size, how to interpret the juveniles?). For the habitat, the specimens grow up in what remains of a tree whose trunk was stained, surrounded by moss.
Since I would like to be enlightened, I attached some more images of the specimen obtained at home. At least we can say that it belongs to the genus Xylaria? or should we leave it with a qualifier as informative as Xylariaceae?

A proper forum
By: Paul Derbyshire (Twizzler)
2010-06-28 06:25:22 CEST (+0200)

Curecat appears to have played a role in creating a Facebook group for MO, which includes a discussion forum.

Yes and no.
By: Danny Newman (myxomop)
2010-06-28 04:35:06 CEST (+0200)

Short a proper forum (wink nudge Nathan), observations are the only place larger discussions can ensue on such topics as general taxonomy, among other things. I have rather unceremoniously hijacked your observation for this purpose because I find it a fitting example of a trend in the treatment of Xylaria spp; the use of only a small handful of epithets to describe what appears to be many more species. It’s nothing personal. As previously mentioned, your ID could very well be the correct one.

Here is the description of X. polymorpha from The North American Pyrenomycetes: A contribution to mycologic botany by J B Ellis, B M Everhart (http://tinyurl.com/TNAPM)

Stromata solitary or 2-6 or more cespitose-connected at base, upright, either simple or cylindrical subattenuated above and below, mostly obtuse; or obovote, compressed, more or less sublobate divided, globose or otherwise irregular in shape, thick, bare, at first dirty-brown, becoming black, not shining, very variable in size from 2-4 cm. high and 1/2 cm. thick to 8-11 cm. high and 2-3 cm. thick. Perithecia crowded, tolerably large, ovate or globose, with a papilliform ostiolum. Asci cylindrical, long stipitate, 8-spored, 140-180 (p. sp) x 8-10 ц. Sporidia uniseriate, elliptical or fusoid, subacute at the ends, subinequilateral or curved, continuous, brown, 20-30 × 6-9 ц.
On decaying stumps and logs, common.
The head or perithecia bearing part is much longer and larger than the stipe which is very short or almost none.

Did I do something wrong?
By: zaca
2010-06-28 01:05:32 CEST (+0200)

I do not understand the motivations of the previous comment.

By: Danny Newman (myxomop)
2010-06-26 20:31:10 CEST (+0200)

is represented at MO in name only in the form of X. hypoxylon and X. polymorpha, predominantly, and to a much lesser extent X. magnoliae, X. tentacula, and X. digitata, with the rest as unknowns lumped into Xylariaceae or the Xylariales as best guesses going on general appearance. How Xylaria and Xylariacious fungi are truly represented at MO we will perhaps never know, or at least not for quite some time, certainly not until an expert shows up, but the diversity is without a doubt well beyond what the naming here at the site suggests. I’ve gotten all long winded on this observation in particular because at a time when entire genera are being axed and/or revamped on the basis of the misapplication of European names to species found in the west, slapping X. polymorpha (what a name, really) on yet another nondescript, black, lignicolous, pudgy thingy, regardless of its country of origin, is suspect. That’s not to say this isn’t X. polymorpha, but it is to say that both a clean-up and fairer future treatment of Xylariacious fungi are in order, which implicates this observation as much as any other.

Created: 2010-06-26 19:41:43 CEST (+0200)
Last modified: 2016-08-31 16:24:07 CEST (+0200)
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